Laryngeal handshake technique in locating the cricothyroid membrane: a non-randomised comparative study

Area of Science:

• Anesthesiology
• Emergency Medicine
• Anatomy

Background:

• Accurate identification of the cricothyroid membrane (CTM) is critical for front of neck airway access.
• Traditional palpation methods often lead to misidentification of the CTM.
• The 'laryngeal handshake' is the currently recommended technique by the Difficult Airway Society.

Purpose of the Study:

• To evaluate the accuracy of the 'laryngeal handshake' technique for identifying the cricothyroid membrane in females.
• To compare the 'laryngeal handshake' with conventional palpation in terms of accuracy, time, and perceived difficulty.

Main Methods:

• Five clinicians used the 'laryngeal handshake' to identify the CTM in 45 anesthetized females (Group L).
• A control group (Group P) of 45 females underwent conventional palpation.
• Ultrasound was used to measure the distance to the CTM, and time to identification and perceived difficulty were recorded.

Main Results:

• The 'laryngeal handshake' resulted in successful CTM identification in 62% of cases, compared to 33% with conventional palpation (P=0.006).
• The distance to the CTM and perceived difficulty were significantly reduced with the 'laryngeal handshake' (P=0.012).
• Identification time was longer with the 'laryngeal handshake' (31s vs 18s, P<0.001), and midline accuracy was higher (39/45 vs 28/45, P=0.008).

Conclusions:

• The 'laryngeal handshake' is a more accurate method for locating the cricothyroid membrane and midline compared to conventional palpation in females.
• While more accurate, the 'laryngeal handshake' requires more time for identification.
• This technique is particularly relevant for front of neck airway procedures where anatomical landmarks may be indistinct.